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(CNN) -- In the coming weeks and months, the dead may outnumber the living in St. Gabriel, Louisiana. Some 6,000 people live in this rural town about 70 miles from New Orleans, but 25,000 body bags are waiting.

St. Gabriel, already home to a women's prison and a former leper colony, is where the grisly work of identifying Hurricane Katrina's dead has begun.

Corpses, plucked from the sodden streets and attics of New Orleans and surrounding parishes, are being brought under police escort in refrigerated trucks to the Federal Emergency Management Agency's temporary morgue. Each body will be assigned a number, but not all may be given names. (Watch the preparations at St. Gabriel -- 2:56)

With more than 100 forensic experts working around the clock, authorities expect to examine, photograph and collect DNA samples from up to 140 bodies a day in what is, in effect, an assembly line of death.

Dr. Louis Cataldie, Louisiana's chief medical examiner, is in charge of St. Gabriel's makeshift morgue. Although the work will be grueling and grim, he told CNN the bodies will be handled with respect for the people who once lived.

"I think it's important for everybody to understand that it's about the individual," Cataldie said. "It's about the little lady with the big brown eyes who is in the Superdome in all that filth who looks at you and you can't do anything for. And somebody hands you a limp kid. And when you come back to her, she's dead. "

"It's about the individual. It's about the one. And I don't want people to lose track of that. We handle every person as the individual and with the dignity they deserve. "

The morgue is set up in stations. Each body that comes in is washed and decontaminated, then assigned a number, a folder and an escort that will follow it though the various stations.

First, a forensic pathologist examines the body. If the person died as a result of the hurricane, photographs are taken. Personal effects such as jewelry are inventoried and photographed to help with identification. Fingerprints are collected, if possible.

Full autopsies will be performed only if there are are signs that death came as a result of foul play.

A full X-ray may be ordered. If the person had an artificial hip or pacemaker, that can lead to an identification because the devices, especially newer ones, are marked with serial numbers. The body then moves to a station for dental examinations and X-rays.

The final stop is the DNA area, where a sample is taken from the victim's femur and stored in a freezer. Then, the body and personal effects are placed in a body bag and returned to a refrigeration truck.

Experts familiar with the grim details of mass deaths say identifying many of Katrina's victims will be all but impossible.

"There is going to be a large percentage of people who remain unidentified," said Dr. Kris Sperry, Georgia's chief medical examiner. Sperry's office spent $1 million on DNA tests to identify about a third of the 339 corpses found at a North Georgia crematory in 2002.

Past disasters have been the forensic experts' best teachers. After the crash of Flight 800 in 1996, all 230 passengers were identified though DNA. It took 13 months. Slightly more than half of the 2,749 people known to have been killed at the World Trade Center were identified through their remains.

Forensic experts say Hurricane Katrina brings its own set of challenges in identifying its victims: The vast number of displaced people; the flooding of dental and medical offices and inaccessibility of records, the contamination of potential DNA samples and the conditions of the bodies themselves.

Unlike plane crashes, or even the terror attacks at the World Trade Center, Katrina and the ensuing flood left an untold number of dead scattered over a wide area. A hurricane has no office directory, no manifest.

"No one knows how many dead there are, especially in New Orleans," Sperry said. "The higher the number of dead, the harder it is to recover all of them and identify them."

Decomposing bodies and skeletons will be recovered, probably for years," Sperry added. "Bodies are buried under rubble, there are bodies in attics."

The environmental conditions pose a far greater challenge.

"Water and muck are being pumped out of New Orleans, and no one has a clue what's under all of that," Sperry said. "It's an incredible teeming soup of bacteria. It makes it more difficult in handling bodies."

He added, "Living people have to be careful handling them. The bodies are not a hazard, the gunk they're floating in is."

Many of the bodies will arrive intact but in poor condition from exposure to heat, humidity and water. And, some of them may have been carried by floodwaters far from where the person lived.

Passers-by who came across floating corpses were told to tie them to trees or street signs. Officials who recovered them recorded the location, using global positioning devices.

"Being in the water that long makes visual identification essentially an impossibility," Cataldie told CNN.

"We'll look for things like identifying marks such as tattoos and personal effects. We'll get DNA. We'll do X-rays if they have prostheses and we'll do fingerprints if we can."

Kerry, who spent last weekend helping at the Federal Emergency Management Agency's morgue in Mississippi, said his colleagues know they have a daunting task ahead.

"They know pretty much this is going to be a long, prolonged grueling sort of thing, that the numbers are going to be very, very high," Sperry said. "An awful lot of folks are unaccounted for. Identifying all these people will be much more massive than what 9/11 was."